Machine-gun synchronizer



July 13, 1926.,

/zari awua Eobcrb Kauai ATRNEY c. IL. PAULUS ET AL MACHINE GUN SYNCHRONIZER Filed May a, 1925 a gun, and

Patented July l3, 1926.

UNITED CHARLES L. PAULUS AND ROBERT KAUCH, @F DAYTON, OHIO.

MACHINE-GUN SYNCHNIZEB.

Application filed in. e, was. s mi No. aaeau.

This invention relates to aircraft machine gun synchronizers, and more particularly to a synchronizer operated by the intermittent explosion pressure impulses of one of the cylinders of the engine of an aircraft The principal object of the invention 15 to provide a machine gun synchronizer consisting of a valve tapped into the rearmost engine cylinder and normally held closed, I) to be opened on] so long as the delivery of pressure impu ses to the machine gun is desired, and a trigger motor on the machine gun connected through a pressure line with the valve, the latter being controlled 5 through a suitable cable extendingto a lever mounted preferably on the joy-stick to enable the operation of the valve to fire the gun in the control of the ship.

Other objects of the invention w1ll be o brought out in the course of the following description, in which reference is made to the accompanying drawing illustrating the invention.

Fig. 1 of the drawing is a'more or less diagrammatic view of a machine synchronizer installation, made in accordance with our invention.

Fig. 2 is an'enlarged longitudinal section through the trigger motor of the machine Fig. 3 is an enlarged isolated detail showing the valve and its operating connection. Referring to the drawing, the reference numeral indicates the engine having a a propeller 11,mounted on its crankshaft 12.

The machine gun 13, mounted on the aircraft at some point to the rear of the engine to be under the control of the pilot or gunner, is arranged to fire between the h blades of the vpropeller 11. The machine gun is provided with a trigger motor 14'. which 1 receives intermittent ressure through a line 15 exten ing from a valve 16 tapped into the rearmost cylinder of the is engine 10. The valve 16 is controlled b a wire assing through a flexible casing 1 of the owden e, which extends cm the valve to the di drpit of the pilot or gun ner .where a hand lever 18 is provided for 0 manual operation. In the form illustrated this lever is shownpivoted on a bracket 19 carried on the joystick20 inthe pilots cockpit. Depending on which one ,of the cylin ders the valve 16'is mounted, it will be seen is that the pressure impulses will occur'at dif ferent intervals of crankshaft travel. It

impulses is therefore necessary to locate the propeller 11 in proper angularity to enable firing between the blades as it turns. For this purpose a dowel pin 21 is provided conveniently on a flange 22 of the propeller mounting which will be engaged in a location hole provided in the hub of the propeller whenthe propeller is installed.

The valve 16 has a lever 23 which is normally held in closed position by a spring 24' acting between a clip 25, pivoted to the end of the lever 23 and a bracket 26 on the side of the valve 16. The control wire 27 in the casing 17 previously referred to, has connection with the. clip and at its 0 posite end with the lever 18 in a suita e manner, and when the joy-stick 20 is grasped it is possible at the same time to hold the lever 18 with the valve 16 opened. In this way the machine gun 13 can be fired so long as desired, while the pilot is maneuvering the ship. An advantage in the provision of a valve which is normally closed is that no power of the en ine is consumed uselessly at a time when t e gun is not to be fired and the life of the mechanism is also increased.

The trigger motor 14 comprises a base 28 mounted in any suitable manner on the side of the machine gun adjacent the trigger mechanism and held suitably by a bolt 29. The motor consists of a cylinder 30 which communicates through the pressure line 15 previously referred to, with the valve 16 on the en v cylinder. A nipple 31, threadin into to open end of the c linder, is provi ed for connection with t e semiflexible tubing, of which the pressure line 15 consists. A piston 32 is reciprocalole in the cyl: inder 30 under the pressure impulses communicated through the line 15 from the engine cylinder, hut is normally held in an inthe inner end of the cylinder.

"A trigger operating plunger 34 is reciprocable an held from rotation in a guideway 35 extending transversely with respect to the cylinder 30 in the base 28. The plunger 34:

has a cam-shaped end 36 projecting into the cylinder 30 into a notch 3 in the slde of the piston 32. The plunger 34 is normally-held man inoperative position by a spring 38 when, the piston 32'is in its normal inoperative position. The intermittent pressure impulses delivered to the piston 32 reciprocate a5 the cylinders of'said engine, spring means the plunger 34 to fire the gun 13. When the propeller 11 has been properly located as above described, it is insured that these power impulses will occur at the proper interdnotely controlling said valve, a machine gun remotely situated with respect to said engine, and a trigger motor for said machine gun having a pressure line extending from said valve to deliver intermittent pressure impulses for the operation of said machine 2. In a machine gun synchronizer for aircraft, the combination with the engine and propeller of said aircraft, of a valve having communication with the interior of one of the cylinders of said engine, spring means normally holding said valve in closed position, a remotely located manually operated lever for holding said valve opened against the s ring pressure for the length of time it is esired to firethe gun, a machine gun remotely located with respect to said engine, a trigger motor mounted thereon, and a pressure line connection for said motor with said valve.

3. In a machine gun synchronizer for aircraft, the combination with the engine and propeller of said aircraft, of a valve having communication with the interior of one of normally holding said valve in closed position, a remotely located manually operated lever for holding said valve opened against the spring pressure for the len h of time it is desired to fire the gun, sai lever being mounted on the joystick of said aircraft to be operated while gripping the stick in the control of the ship, a machine gun remotely located with respect to said en ine, a trigger motor mounted thereon, an a pressure line connection for said motor with said Valve.

4. An engine pressure operated impulse device comprising a manually controlled valve tapped into the engine cylinder, a tube leading therefrom, an impulse cylinder connected to the far end of said tube, a piston in said cylinder to be operated from a normal inoperative position by intermittent pressure impulses from the cylinder communicated through said tube, and means operated by said piston.

5. An engine pressure operated impulse device comprising a manually controlled valve tapped into the engine cylinder heldnormally in closed position under spring pressure to be held 'open manually so long as operation of the impulse device is desired, a tube leading from said valve, an impulse cylinder connected to the far end of said tube, a spring pressed piston operating in said cylinder-to be'moved against the spring pressure by the engine pressure impulses, and means operated by said piston.

In testimony whereof we afiix our signatures. CHARLES L. PAULUS.

ROBERT KAUOH. 

